Your fridge and freezer work quietly, every hour of the day, and they collect far more than you might expect: crumbs in the salad drawer, a sticky ring beneath the jam jar, and that faint smell you can't quite place near the ice tray. A proper deep clean takes about an hour, costs very little, and does more than make things look tidy. Clean seals and clear vents help your appliances run efficiently, which keeps food fresher for longer and takes pressure off your energy bills.

Why a deep clean pays off

The inside of a fridge is a surprisingly demanding environment. Spills and crumbs feed bacteria, and because many foods are eaten raw, cross-contamination matters. A weak door seal lets cold air escape, so the compressor runs longer and harder than it should. Dusty condenser coils at the back or beneath the unit trap heat and waste electricity. A blocked drain hole at the rear of the fridge leaves water pooling under the salad drawer, which is a common cause of lingering smells.

None of this requires specialist equipment. Warm water, a mild food-safe cleaner, a couple of cloths and a little patience will do the job properly.

Empty it safely before you start

Timing matters. Choose a day before your food shop if you can, so there is less to move. Have a cool bag or two ready with ice packs, plus a few tea towels or sheets of newspaper for extra insulation.

• Keep chilled food out of the cold for as short a time as possible — aim for under an hour in total, and never leave it near a radiator or in direct sun.
• Check dates as you unload. Bin anything past its use-by date and set aside anything that needs eating first.
• Remove all removable parts — shelves, drawers, door bins, egg trays and ice cube trays.
• Switch off at the plug if you are defrosting the freezer or cleaning the coils. For a standard fridge clean, you can leave it running.

Clean surfaces with food-safe products

Whatever you use will sit close to your food, so keep it simple and gentle. A tablespoon of bicarbonate of soda dissolved in a litre of warm water is excellent for wiping walls and lifting light grease, and it neutralises odours as it goes. For glass shelves and sticky marks, a fifty-fifty mix of white vinegar and water works well. A few drops of unscented washing-up liquid in warm water is fine for general wiping.

• Avoid bleach, abrasive creams and heavily perfumed sprays on surfaces that touch food, and never use oven cleaner or solvent-based products.
• Let cold glass shelves reach room temperature before washing them. Cold glass can shatter if it meets very warm water.
• Work from the top down, and wipe the floor of the fridge last, where drips collect.
• Dry everything with a clean cloth rather than leaving it damp, then let the door stand open for ten minutes to air.
• Don't overlook the runners, the underside of shelves and the door bins — these are often the grimiest parts.

Check the seals, vents and drain hole

The working parts deserve as much attention as the shelves. Wipe door seals with warm soapy water and dry them thoroughly, then run a finger around the whole seal looking for splits or hardened patches. To test the grip, close the door on a strip of paper; if it slides out easily at that point, the seal is probably due for replacement. Avoid smearing oil or petroleum jelly on rubber seals, as this can degrade them over time.

Wipe interior vents with a dry cloth and take care not to block them with tall bottles or overfilled drawers — good air circulation is what keeps temperatures even. At the back of the fridge you will usually find a small drain hole; clear it with a cocktail stick or pipe cleaner, then flush it gently with warm water. If you can reach the condenser coils, unplug the appliance first and dust them with a vacuum brush attachment once or twice a year.

Reorganise with zones and dates

How you reload the fridge decides how long it stays clean. Cool air sinks, so place ready-to-eat foods, leftovers and dairy on the upper shelves, and raw meat and fish in sealed containers on the bottom shelf where nothing can drip onto anything else. The salad drawer is for vegetables and fruit, and the door — the warmest spot — suits condiments, drinks and butter rather than milk.

• Rotate stock: new items go behind older ones so nothing gets forgotten.
• Decant into clear containers and label with the date, especially for leftovers and batch cooking.
• In the freezer, freeze flat in bags and stack upright, or use baskets so you can see what you have.
• Leave a little breathing room. Fridges need airflow; freezers work best when fairly full but not crammed.
• Keep an open dish of bicarbonate of soda on a shelf to absorb odours, and replace it every couple of months.

Simple habits between deep cleans

Wipe spills as they happen and check dates once a week — it takes two minutes and prevents most of the mess. Once a month, give the shelves a quick wipe, glance at the seals and check your temperatures: your fridge should sit between 0°C and 5°C, and your freezer at -18°C. A full deep clean every three to four months is plenty, plus a thorough one after a power cut or a defrost. If food near the door starts spoiling early, that is your cue that the seal or the temperature needs attention. Look after these appliances and they will quietly look after your food.